Back pain is the number one cause of worker-compensation complaints, second only to the common cold in causing lost workdays. Consequently, employers and regulators have pushed training programs to teach specific lifting methods, and some recommend or require the use of assistive devices such as hoists for hospital workers. However, a new review of the research on lifting advice and handling devices has found that they do not prevent work-related back pain.

“According to the studies we have so far, it seems that this is not effective,” said lead author Kari-Pekka Martimo, of the Finnish Institute of Occupational Health in Helsinki. He and his colleagues examined data from more than 18,000 employees in eleven studies. Some studies looked at advice or assistive devices alone and some looked at combining both, but the combinations did not prove effective either. The advice and devices did not prevent back pain or reduce disability claims or sick leave.

According to Martimo, one explanation for the negative findings could be that “safer” lifting techniques do not really exist — so teaching particular tactics would be unlikely to help. “Another possibility is that elevated risk for back pain might not be related to lifting or moving heavy objects themselves, but to other aspects of work,” he said. High stress, for example, might link jobs that require lifting to back pain, rather than the lifting itself. Alternatively, it could be that the teaching is the problem — and that workers do not actually adopt better habits.

“This study confirms that much of what is happening at the workplace is well-intentioned but probably pointless,” said Christopher Maher, associate professor of physiotherapy at the University of Sydney in Australia. “This study really does confirm that we need to take a fresh look at the problem,” Maher said.